rb20 stalling problems..HELP!!!

[rbchick]

alright so about a week ago( when it started getting REAL cold in nj) i was stopped at a stop sign on a slight hill. i go to go through the stop sign and my car stalls out. assuming that it was just my mistake i try to start my car after a few times i start smelling a gas fume smell but it doesnt start so i use the hill to roll it backwords onto a side street that was a few feet away. my car still didnt start. after about 10 minutes finally it starts and i get it home. i investigate and dont see anything leaking from the engine (besides a little oil). the next day i go to drive it to school and while getting stuck at another stopsign on a hill the car stalls again. but this time it starts right back up and continues to go. then i get to school and while going over a speed bump (which is on a slight incline) the car stalls again and eventually starts back up.
it seems to be an ongoing problem and im really not sure whats wrong.
i dont know if this would lead to anything but my turbo is done, and my yesturday my radiator said its last goodbyes and finally crapped out on me.

but what could this stalling problem be? could it just be the temperature outside?